median — 2D rank op

• Data kinds: image → image

• Call: fullseye.apply(img, "median", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

• HALCON equivalent: median_image (the HALCON reference is a useful guide to its meaning and parameters)

Usage

Median filter. Equivalent to HALCON's `median_image` (Compute a median filter with various masks.).

> The detailed description below is the original text — the summary and the headings are translated.

`a が窓サイズを 3,5,7,9（_k(a)）に振る。b` は未使用。塩胡椒ノイズなど外れ値に強く、ガウシアン平滑よりエッジを保ちやすい。

Detailed usage guide

• gallery2d_smoothing_rank family guide

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• astro_stacking — py -3.11 examples/astro_stacking.py

• consumer_onocollo — py -3.11 examples/consumer_onocollo.py

• ct_reconstruction — py -3.11 examples/ct_reconstruction.py

• gallery2d_smoothing_rank — py -3.11 examples/gallery2d_smoothing_rank.py

• lightfield_depth — py -3.11 examples/lightfield_depth.py

• machined_metal_and_materials — py -3.11 examples/machined_metal_and_materials.py

• perception_pipeline — py -3.11 examples/perception_pipeline.py

• photon_timeresolved — py -3.11 examples/photon_timeresolved.py

• quickstart — py -3.11 examples/quickstart.py

• representation_roundtrip — py -3.11 examples/representation_roundtrip.py

• specular_photometric — py -3.11 examples/specular_photometric.py

Ops the type connects to (they accept image as input)

identity · gaussian · mean_box · bilateral · unsharp · min_filter · max_filter · percentile

Same category (rank)

min_filter · max_filter · percentile · sk_median_disk · cv_median · median_image · median_rect · median_separate

*Provenance: ops.py — 2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.